Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id B440B1337B50 for ; Wed, 24 Nov 2010 11:16:56 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 86689-06 for ; Wed, 24 Nov 2010 15:16:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id E884E1337B4E for ; Wed, 24 Nov 2010 11:16:48 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id oAOFGm3e018331; Wed, 24 Nov 2010 10:16:48 -0500 (EST) To: Elliot Chance cc: pgsql-admin@postgresql.org Subject: Re: pg_dump and XID limit In-reply-to: References: <6420.1290578869@sss.pgh.pa.us> Comments: In-reply-to Elliot Chance message dated "Wed, 24 Nov 2010 20:59:59 +1100" Date: Wed, 24 Nov 2010 10:16:48 -0500 Message-ID: <18330.1290611808@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.91 tagged_above=-10 required=5 tests=BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201011/216 X-Sequence-Number: 36182 Elliot Chance writes: > Wouldn't that mean at some point it would be advisable to be using 64bit transaction IDs? Or would that change too much of the codebase? It's not so much "too much of the codebase" as "nobody wants another 8 bytes added to per-row overhead". Holding a transaction open for circa 2G transactions would be disastrous anyway, because of table bloat from inability to reclaim dead rows. regards, tom lane